(1) Field of the Invention
The present invention relates to the launching of vehicles from the submerged hulls of vessels, and more particularly, to the launching of vehicles such as torpedoes, missiles, mines, countermeasures and autonomous underwater vehicles (AUV's), from the hull of a submarine.
(2) Description of the Prior Art
Conventionally, vehicles such as torpedoes, missiles, mines, or countermeasures (hereafter called vehicles) are launched from a submarine hull through a torpedo or launch tube. The launching imparts longitudinal motion of the vehicle through the tube, which carries the vehicle down the tube and out of the submarine hull form into the water flow stream outside the moving hull.
In general, the vehicle is launched either obliquely against, or normal (perpendicular) to, the flow stream outside the moving hull. In order for the vehicle to clear the hull, it is propelled initially by pumped water or compressed air introduced behind the vehicle in the tube. A significant amount of energy with consequent acoustic noise generation, is associated with the launch. Not only does the conventional launch technique create significant acoustic noise, but the ejection system requires substantial volume and weight allowances internal to the submarine.
Because the vehicle is constrained by the launch tube walls from freely reacting to the hydrodynamic force due to the flow field (which urges the vehicle to yaw and translate off the launch tube axis), the vehicle can experience damage from impact and varying loads while riding on or hitting against the launch tube wall. Also, the resulting disruption to the intended trajectory can prevent the vehicle from stabilizing after launch. Moreover, vehicle designs are limited to configurations and geometries that can interface with, and accommodate contact against, the tube during launch. In many cases, the submarine speed related launch envelope is restricted to prevent damage to the vehicle or to insure controllability.